Objective: To analyze the application of mental model based on relaxation training combined with 5E rehabilitation model in patients with coronary heart disease undergoing PCI and its influence on their psychological burden and self-management behavior. Methods: 92 cases of patients who were treated with PCI in our hospital from July 2021 to July 2024 due to coronary heart disease were selected and divided into groups according to computer random number table method. 46 cases of patients in the control group were given routine nursing, and 46 cases of patients in the observation group were given mental model based on relaxation training combined with 5E rehabilitation mode. The psychological burden, self-management behavior, recovery of heart function and exercise endurance of the two groups were compared. Results: After nursing, in the observation group, the PHQ-9 score and GAD-7 score were (10.41±2.22) points and (9.76±2.10) points, which were lower than (13.05±2.37) points and (11.18±2.23) points those of the control group, respectively (P < 0.05). In the observation group, the CSMS score was (99.86±13.30) points, which was higher than (91.21±12.79) points that of the control group (P < 0.05). In the observation group, the LVEDD and LVESD were lower than the control group, while the LVEF was higher than the control group (P < 0.05). In the observation group, the 6MWT was far higher than the control group, and the VO2peak and VO2AT were also higher than the control group (P < 0.05). Conclusion: For patients with coronary heart disease after PCI, the combination of mental mode based on relaxation training and 5E rehabilitation mode can not only relieve their psychological burden and improve self-management behavior, but also improve the recovery effect of cardiac function and enhance their exercise endurance.